It's a portmanteau of "nigh" and "Siren."
Two of the three Autobot Small Headmasters differed between North America and Japan -- Hosehead was no different from Cab, Nightbeat was drastically different from Minerva, and Siren was... sort of different from Goshooter. While Siren's toy was a gray and blue fire chief car, Goshooter was a white and blue police car. Thing is, when Siren appeared in the Marvel Comics back in the 80s, his grays were rendered as white, so in my brain there is very little difference between the two. Marvel Comics Siren is what inhabits me, and so when I see Goshooter, I think "oh, hey, Siren."
So I was all over this new Japan-exclusive version of Goshooter made from Generations Nightbeat. (Another wrinkle in all this is that the Marvel comics swapped head designs for Nightbeat and Siren, meaning Nightbeat's head is pretty damn appropriate for a Goshooter toy.) Goshooter was the winner of a magazine poll that offered ten redeco concepts -- other possibilities included Alpha Trion from Scourge, the Omnibots from various Universe/Generations toys, Beast Wars Silverbolt from Beast Hunters Grimwing, and crazily enough The Fallen from Fall of Cybertron Onslaught. All of these concepts showed up in the magazine's manga, including The Fallen, who combined with and controlled the Fall of Cybertron Wreckers. Of all of these, I was hoping for Goshooter the most, so I could use him as Siren, and the universe ultimately smiled upon me. I mean, I wouldn't have turned down another The Fallen, but I have plenty of The Fallens and only the original Siren, who is an immobile giant thing.
Goshooter comes with Shuta Go, a redeco of Blazemaster meant to represent Goshooter's human pilot. I figure he can hang out with Daniel and Stylor.
Goshooter is extravagently decoed, though it has some trouble dealing with the unpaintable nylon plastic that makes up part of the car shell, resulting in some incongruous blue patches. Also, my particular Goshooter is pretty floppy in the ankles, and so at times he has trouble standing. Otherwise, he completes my desire for new toys of the Small Headmasters, along with my Nightbeat (with new chest I got from Shapeways) and Hosehead (who's really a Hot Spot with an altered head). All three are on the Lost Light in More Than Meets The Eye, so that's more crewmembers for that display, too.
Hooray! Goshooter and/or Siren!